Minase 5 Windows “One” Masterpiece Review

by Jan 30, 2020Limited Edition, Minase

Japan has a few well established watch manufacturers, such as Seiko, Grand Seiko, Citizen and Casio, however most would not fall into the “luxury” or “exclusive” categories.  

Minase, however, is Japan’s smallest watch manufacturer and is chasing on the heels of the Swiss watch brands when it comes to design and craftsmanship. 

Minase have taken their most original model, which was designed by its creator, Hirokuni Yamamoto.  The creation of the 5 Windows model broke down all design concepts he had learnt and practiced during 30 years of experience. 

The Minase “One” is based on the 5 Windows design and is the first watch of the Champlevé Serie, which in turn is part of the Masterpiece Series of exclusive watches.  

The first model of the Champlevé Serie pays tribute to Akita Prefecture of clear spring water, ducks and maple leaves – Minase explain the concept of the “One” below, with a little more eloquence:

At Minase, we do not only want to create beautiful watches, we aim to produce little pieces of Japan.  Every watch is hand-made, with traditional techniques and a deep know-how from the craftsmen, each watch carries a story.  With our Masterpieces Collection, we wanted to create timepieces that are even more rare, unique and beautiful.  The Minase One belongs to the Masterpiece collection and features a hand-painted enamel dial inside a palladium case.  The Minase One praises Akita Prefecture, where Minase was born, depicting the famous ducks, excellent water and the maple trees.

Minase 5 Windows "One" Masterpiece

Minase 5 Windows “One” Masterpiece

Face & case

Minase watches are manufactured using traditional methods and craftsmanship, however the design of many of their pieces do not really conform to the “classic” case and dial design we are used to seeing.

As in all Minase 5 Windows models, the construction method is of case-in-case, where the round dial is situated in an internal case, within a larger box-type case of a completely different shape.

On this occasion, the outer box case is made from palladium, with 5 sapphire crystal “windows” (front, back and left having one “window” each, with the right side having one “window” on either side of the crown), allowing the internal case to be viewed from multiple angles.  

The window “frames” are substantial and angular, with both polished and brushed edges to accent the different angles of the case.

This version of the Minase 5 Windows being reviewed is classed as their “regular size” and with the outer case at 38mm wide by 46.5mm high, there is plenty of room for a second case within it.

The oval shaped inner case, of which it’s edges of the inner bezel are tucked beneath the outer case, appears on first glance not to be fixed to anything and therefor almost floating, but look closer and you will see the fixing plate and screws tucked down into each of the four corners.

The fixing plate appears to act almost like a clamp holding the inner case together from beneath, with polished “claws” visible in 12 locations around the edge of the bezel, which also act as functional hour markers and add to the ease of reading the time.

Moving in, the bezel (in a non traditional sense) is quite wide, with a brushed angular edge and a polished top side.  At 6 o’clock, there are 4 little engravings, two kanjis and a flower on either side to the left and right of them.  Kanjis are Chinese graphical characters used in Japanese writing, primarily to display content words (nouns, adjective stems, and verb stems)  and these 2 particular kanjis represent Minase.

The “bezel” frames the dial, which unlike the other versions in the 5 Windows range, does not have a date function, as all focus is on the dial itself.

The star of the show is the dial, which is made using Champlevé enamel, featuring art by Japanese artist Kenji Kanagawa.  Starting with a solid silver plate, the image is hand engraved to form the beautiful scene of ducks on water with maple leaves, hand painted in blues, oranges and brown colours.  Notice how thin the borders between the colours are. 

Using this method means that every dial will be unique by default.

Sitting above the dial, are the hands.  Although they are in the same metal as their surrounding, they are relatively wide and therefor there is no problem reading the time.  Look closely and you will see the hands are actually slightly curved at the tip in order to match the dial’s shape.

The crown appears oversized, but a lot of thought has gone into it too.  Featured in all of Minase’s pieces, the brand’s logo is clear at the end of the signature polyhedral crown, which offers great grip.

On the reverse, the screw down case back features one large window.  The fixing plate and bottom of the case can be seen circling the winding rotor, with the bottoms of the screws used to fix the “clamp” mentioned earlier also visible.  

Unlike many winding rotors, this one is circular, rather than semi circular or axe shaped.  This leaves room for more aesthetics – 2 different types of geometric pattern can be seen on the rotor, one inside and the other outside a blue outlined diamond shape.  Breaching the diamond shape on 2 of it’s sides are 2 large red kanjis.  This particular piece is owned by a Japanese customer who requested these specific kanjis and one can only assume they have some significance to the owner.

On the frame there are various very light engravings, such as “Water Resistant” (to 50m), “Japan” and “Stainless Steel” at the bottom and “HiZ Series” at the top.

“HiZ” is a concept inspired by the Japanese words “Hizu” (exceptional) and “Hi Izuru Kuni” (Land of the Rising Sun).  Minase products labelled “HiZ” are unique and innovative.

Minase 5 Windows "One" Masterpiece Case Back

Minase 5 Windows “One” Masterpiece Crown


An automatic ETA 2892 caliber has been modified by Minase, with a customised mass, ceramic bearings, blue screws and bridges decorated by drilling.

It’s heart beats at 28,800 vph and owners should expect up to 42 hours of power reserve once fully wound.

Minase 5 Windows "One" Masterpiece Crown

Minase 5 Windows “One” Masterpiece Crown


The strap is black alligator with thick grey stitching and a black cowhide lining, with a large, angular buckle made from palladium, with both brushed and polished finished edges.

Minase 5 Windows "One" Masterpiece Strap and Buckle

Minase 5 Windows “One” Masterpiece Strap and Buckle

Minase 5 Windows “One” Masterpiece Strap and Buckle

Other stuff

Minase is owned by a renowned tool manufacturer, Kyowa, specialising in step drills and which also supplies of high-end watch components.  The logo on the crown is that of a drill-head that pays homage to the origins of the parent company.

MINASE timepieces embody the Japanese key principle “Monozukuri”,  Simply translated as “Japanese manufacturing style”, Monozukuru is more a state of mind and philosophy of work, which is constantly striving to output excellence, whilst at the same time improving both products and processes.  Every worker at Minase is 100% committed to these traditions, with pride and passion in order to create perpetual excellence.

Along with the “HiZ” concept, which includes features such as the case in case structure and the “Sallaz” polishing technique, Minase has come up with the “MORE” (Minase Original Rebuild Equation) construction principle.  “MORE” construction is inspired by the ancient mastery of 3-dimensional wood puzzles (Ysegi-Zaiku).  By using this technique, most Minase watches and their bracelets can be easily disassembled, so that the products can continue to shine as well as on the first day it was worn. 

Minase 5 Windows "One" Masterpiece on the Wrist

Minase 5 Windows “One” Masterpiece on the Wrist

Minase 5 Windows “One” Masterpiece on the Wrist

Our verdict

When I first saw watches by Minase, I wasn’t too sure about what I was looking at.  I can’t really explain why; perhaps it was the fact that they appeared a bit different, but as our readers know, my taste can be a bit eccentric, so that’s not a great reason!

However, after spending a bit of time with this watch and learning about the brand and the concept and tradition behind it, I have started to warm to both the design and appreciate the manufacturing techniques.  

Along with looking fantastic, the watch feels sturdy in hand and fits well, with the relatively large case well balanced across my wrist and still feeling as if it’s got some weight to it.  At 14mm deep and with the curved case, it shouldn’t cause too many issues with cuffs. 

I have to be honest and say that although I do like the overall design and concept of the 5 Windows, I would not choose this particular scene from the “One”, as the design feels a bit feminine for me.  I am however told that Minase provide an option that would solve this “problem” – it is possible for clients to choose the enamel dial design of their choice (for an additional charge).  This option can also be requested on any 5 Windows base watch.

Only 8 pieces are being made of the “One” Masterpiece and priced at 34,155 EUR, it’s unlikely you will see one around and even less likely to see an exclusive bespoke piece. 

The good news is that Minase only manufacture around 500 pieces in total per year, so purchasing a standard 5 Windows (or other) Minase watch, would actually put you in a fairly exclusive club!